INVESTIGATION OF USING PAPER INDUSTRY WASTE (HYPO SLUDGE) IN CONCRETE MIX

Abstract

Cement industry is one of the major producers of carbon dioxide gas (a greenhouse gas) and ordinary concrete contains about 12% cement. The world’s annual production of cement is 1.6 billion tons which accounts for about 7% emission of carbon dioxide gas in atmosphere. Concrete industry is consuming large amount of natural resources (gravel, sand, fine rock, water etc). In order to address such environmental issues related to cement manufacturing there is dire need of replacing cement with other binders to be used in concrete. This study investigates the utilization of waste paper sludge ash (WPSA) in concrete. WPSA was partly replaced in the ratios of 5, 10, 15 and 20 percent of cement. Specimens were tested for initial setting time, final setting time, mechanical strengths (i.e. compressive and tensile strength) and dry density, and results are compared with ordinary concrete (without WPSA).The results showed that WPSA can be replaced up to 15% by weight of cement. Also the initial and final setting time of cement are gradually reduced by increasing the percentage of WPSA. The addition of WPSA results in a lighter concrete.